Incorrect Gear Ratio
Table of contents
P0730 OLDSMOBILE Possible Causes
- Low transmission fluid level
- Dirty transmission fluid
- Shift solenoids
- Transmission mechanical problems
- Transmission hydraulic control circuit
How do I fix code P0730 OLDSMOBILE?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
- Start by inspecting the transmission fluid level and condition, and change fluid if necessary.
- There is a factory service bulletin for the following Oldsmobile models:
- 2000-2002 Oldsmobile Intrigue
- 2000-2003 Oldsmobile Aurora
- 2000-2004 Oldsmobile Alero
- 2000-2004 Oldsmobile Silhouette
- Oldsmobile Factory Service Bulletin OBDII Code P0730
Cost of diagnosing the P0730 OLDSMOBILE code
The cost of diagnosing the P0730 OLDSMOBILE code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Incorrect transmission shifting
P0730 OLDSMOBILE Description
This diagnosis monitors the actual gear position by checking the torque converter slip ratio calculated by the Transmission Control Module (TCM) as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from the speed sensor (revolution sensor)
B: Engine speed signal from Engine Control Module (ECM)
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is higher than the position supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.
The Diagnostic Trouble Code (DTC) will set when the TCM has detected that the transmission is trying to mechanically shift to a lower gear than intended.
